The Mobile Vision API is now a part of ML Kit. We strongly encourage you to try it out, as it comes with new capabilities like on-device image labeling! Also, note that we ultimately plan to wind down the Mobile Vision API, with all new on-device ML capabilities released via ML Kit. Feel free to reach out to Firebase support for help.

<GMVOutputTrackerDelegate> Protocol

<GMVOutputTrackerDelegate> Protocol Reference

Overview

Delegate used to receive notifications for a detected item over time.

Inherits <NSObject>.

Instance Method Summary

(void) - dataOutput:detectedFeature:
 Called to initially inform the delegate that a new item has been detected. More...
 
(void) - dataOutput:updateFocusingFeature:forResultSet:
 As a feature is detected over time, this method is called to give an update for the feature in the context of the overall detection. More...
 
(void) - dataOutput:updateMissingFeatures:
 Called if either the tracked feature was not detected at all in a frame, or if the specific feature identity associated with the delegate is not present in the current frame. More...
 
(void) - dataOutputCompletedWithFocusingFeature:
 Called to indicate the feature associated with the tracking ID previously reported via dataOutput:detectedFeature: has been assumed to be gone forever. More...
 

Method Detail

- (void) dataOutput: (GMVDataOutput *)  dataOutput
detectedFeature: (GMVFeature *)  feature 

Called to initially inform the delegate that a new item has been detected.

The tracking ID will remain constant for all calls to dataOutput:updateFocusingFeature:forResultSet: until dataOutputCompletedWithFocusingFeature: is called. dataOutput:updateFeatures:focusingFeature: is always called immediately following this method call, with the same item that was passed into this method.

Parameters
dataOutputThe GMVDataOutput object requesting the call.
featuresThe newly detected GMVFeature.
- (void) dataOutput: (GMVDataOutput *)  dataOutput
updateFocusingFeature: (GMVFeature *)  feature
forResultSet: (NSArray< __kindof GMVFeature * > *)  features 

As a feature is detected over time, this method is called to give an update for the feature in the context of the overall detection.

Each feature that is received has the same tracking ID as it had in the most recent call to dataOutput:detectedFeature:. That is, it has been determined to be the same tracked feature initially seen.

Parameters
dataOutputThe GMVDataOutput object requesting the call.
featureThe GMVFeature associated with the delegate.
featuresThe full detection results.
- (void) dataOutput: (GMVDataOutput *)  dataOutput
updateMissingFeatures: (NSArray< __kindof GMVFeature * > *)  features 

Called if either the tracked feature was not detected at all in a frame, or if the specific feature identity associated with the delegate is not present in the current frame.

It's possible that the feature may be missed for a few frames, and will reappear later, depending upon the detector settings. dataOutput:updateFocusingFeature:forResultSet: would then be called.

Parameters
dataOutputThe GMVDataOutput object requesting the call.
featuresThe full detection results.
- (void) dataOutputCompletedWithFocusingFeature: (GMVDataOutput *)  dataOutput

Called to indicate the feature associated with the tracking ID previously reported via dataOutput:detectedFeature: has been assumed to be gone forever.

Parameters
dataOutputThe GMVDataOutput object requesting the call.